Field of the Invention
This invention relates to the production of mercaptans from olefins, viscous polyolefins and hydrogen sulfide utilizing trifluoromethylsulfonic acid as a catalyst.
It is an object of this invention to provide trifluoromethylsulfonic acid as a catalyst for the manufacture of mercaptans from olefins and viscous polyolefins and hydrogen sulfide and novel beta-polybutenylsulfoxy-alpha-hydroxyethylbenzenes. It is a further object to provide a process for the manufacture of mercaptans which process comprises reacting olefins or polyolefins with hydrogen sulfide in the presence of trifluoromethylsulfonic acid. Further objects and advantages will become apparent as the description of the invention proceeds including the object of providing mercaptans useful in the preparation of nonionic surfactants for lubricating oils and in enhanced oil recovery, as well as for biocides.
One route to the preparation of mercaptans has been the reaction of a primary alkyl halide with sodium hydrosulfide to form the corresponding alkyl mercaptans and sodium chloride. Another prior art method is the reaction of an alcohol with hydrogen sulfide over thoria to obtain the corresponding mercaptans plus water. In U.S. Pat. No. 3,045,053 (1962) a process for reacting olefinically unsaturated compounds with hydrogen sulfide is disclosed. That process comprises carrying out the reaction in the conjoint presence of an organic peroxide and at least one finally divided elemental metal in Group VIII of the Fourth Period of the Periodic Table. U.S. Pat. No. 2,031,601 (1950) discloses the preparation of mercaptans from polymeric olefins utilizing anhydrous aluminum chloride and related Friedel Crafts catalysts.
I have discovered that trifluoromethylsulfonic acid is very effective catalyst for the manufacture of mercaptans from olefins and viscous polyolefins and hydrogen sulfide. A unique feature of this catalyst is that in the olefinic reactions it catalyzes both polymerization and hydrogen sulfide addition in one reaction. When diisobutylene is a reactant along with hydrogen sulfide, mercaptans of molecular weight higher than tertiary octyl mercaptans are produced.
I have discovered a process for the preparation of mercaptans which comprises reacting olefins or polyolefins at a temperature of about 10.degree. to 70.degree. C. with hydrogen sulfide under pressure of about 1 to 10 atmospheres in the presence of about 0.05 to 10 percent by weight of the olefins of trifluoromethylsulfonic acid. My preferred temperature range is 10.degree. to 35.degree. C. and the preferred pressure range is 1 to 5 atmospheres. The mercaptans produced according to my novel process are useful in the preparation of nonionic surfactants for lubricating oils and in enhanced oil recovery as well as for biocides.
A wide variety of olefinically unsaturated organic compounds may be reacted with hydrogen sulfide in accordance with my invention. Suitable charge stocks comprise a wide variety of olefinically unsaturated organic compounds. These may be reacted with hydrogen sulfide in accordance with the invention. Suitable charge stocks comprise ethylene, propylene, butene-1, butene-2, isobutylene, pentene-1, heptene-1, octene-1, dodecene-1, tetradecene-1, or their mixtures, or other alkenyl hydrocarbons. Examples of isoalkenyl compounds suitable for use herewith include 3-methyl butene, 4-methyl pentene, dimethyl hexene, or their mixtures with each other. Aryl olefins may also be used, and are exemplified by styrene, alpha-methyl styrene, etc. Suitable diolefins, which may be reacted to form dimercaptans and olefinically unsaturated mercaptans, include butadiene, piperylene, isoprene, etc., or their admixtures with alkenes; cyclic olefins, such as cyclopentene, methyl cyclopentenes, cyclopentadienes, di-cyclopentadienes, etc.; my preferred olefins are diisobutylene and polybutene. My novel catalyst trifluoromethylsulfonic acid is useful in converting all of the aforementioned olefins with hydrogen sulfide to the appropriate mercaptans. These mercaptans are particularly useful in the preparation of surfactants for lubricating oils and as biocides. I have also discovered as novel composition of matter beta-polybutenylsulfoxy-alpha-hydroxyethylbenzenes and mercaptans of the following formula ##STR1## Usually h=8 but h can have a value from 6 to 10.